Metal-organic framework-based catalysts for hydrogen production from liquid-phase chemical hydrides

Hydrogen is a clean, sustainable, and efficient energy carrier. However, the safe and controllable storage and evolution of hydrogen for practical applications remain challenging. Chemical hydrides, such as metal borohydride, ammonia borane, hydrous hydrazine, hydrazine borane, and formic acid, have been studied as promising hydrogen carriers because of their high hydrogen capacity, excellent safety, easy transportation and storage, and mild dehydrogenation conditions. Developing efficient, selective, and stable catalysts for H2 production from chemical hydrides becomes very important. Recently, metal–organic framework (MOF) materials have been intensively exploited in catalytic hydrogen production reactions on account of their diverse composition, adjustable pore structure, large surface area, high porosity, and tailorable chemistry. Herein, we outline significant progress achieved in MOFs and their composites and derivatives toward catalytic hydrogen production from liquid-phase chemical hydrides. The state-of-the-art synthesis methods and advanced characterization of MOF-based catalysts and their catalytic activities in hydrogen production, are introduced. Finally, the opportunities and challenges for the future development of MOF-based catalysts toward dehydrogenation of chemical hydrides are briefly summarized and prospected. It is believed that this review will provide important understanding and enlightenment for hydrogen evolution from liquid-phase chemical hydrides over MOF-based catalysts.